Record date and time on first non-blank

[MichaelN]

I need ideas on how to record the date and time when the user records data in one column. I only want to record the date and time first enters data in the column and not subsequent changes.

ChangeTimeStamp would almost work but, CSV uploads to the table trigger a change to the column therefore a new timestamp.

[Steve]

Set Reset on edit? to ISBLANK([_THIS]).

Set Initial value to NOW().

Set Editable? to FALSE.